Stabilizing device for aircraft



July 9, 1929." R TEA 1.720.576

STABTLIZING DEVICE FOR AIRCRAFT Filed Aug; 2, 1928 2 Sheets-Sheet 1INVENTOR WITNESSES QB v ATTORNEY July 9, 1929. P. D. STEAD STA BTLIZINGDEVICE FOR AIRCRAFT Filed Aug.2, 1928 2 Sheets-Sheet 2 INVENTOR B D.LSZad ATTORNEY Patented July 9, 1929.

UNITED STATES PHILIP D. STEAD, OF NORFOLK, VIRGINIA.

STABILIZING DEVICE FOR AIRCRElF'l.

Application filed August 2, 1828.

This invention appertains to improvements in stabilizing devices foraircraft gem orally, and has for an object to provide tor a type oi?such devices which will function to minimize or otherwise eliminateaccidents resulting from nose-dives, tailspins and the like oi aeroplanes in flight.

Another object oi? the invention is to provide a device of the class setforth, which is extremely simple but durable and el'licient inconstruction and arrangen'ient of parts, comparatively inexpensive toll'lz'LULliltlCtlllG and easy to install. on standard types and makes ofaircraft.

A tliurther object of? the invention is to provide a device ashereinbeliore characterized, which, when properly installed in positionon an aeroplane, will be entirely automatic in operation. for itsintended purposes, aforesaid.

Nith the foregoing and other equally important objects and advantagesinview, the

invention resides in the certain new and use- :tul combinations,construction and arrangement oi parts as will be hereinafter more tullydescribed, set :iiorth in the appended claims, and illustrated in the:uzcompanying drawin gs, in which:

Figure l is a side elevation of an aeroplane at rest, and showing thepractical embodin'ient oi the invention. applied thereto,

Figure 2 is a similar View, but showing the aeroplane in a position atthe moment of take -oil, and the stabilizer in initial position oil?operation,

Figure 3 another similar view, showing the zlQlOPlitDt, in flight andvthe stabilizer disposed in the full position of operation,

Figure l is an enlarged fragmentary section of the lower side oi thefuselage of an aeroplane an d showing the upper end portion o'tv thestabilizing device in rear elevation and as attached thereto, and

lligure 5 is a view similar to that of Figure 4;, but showing theattached en d portion of the device in side elevation and partly insection.

Referring to the drawings, wherein like characters OIl referencedesignate corresponding parts throughout the several views thereof, theembodiment of the invention, as shown therein by way of example,comprises an el0ngated member 1.0 dependingly supported from theunderside of the fuselage a of: an aeroplane at the point of the centerof balance thereof and through the medium of a sup- Selizll No. 296,982.

portiu memliier or bracket 11 to the rear side of the .lower end oi"which the member is hinged, as a t 12, tor the purpose.

The elongated member 11) is preferably in the form of a flexible orsemi-flexible length of rod. or tubing and tapers towards its lower endwhere it merges into a subsl antially enlarged and prel m-ably thatportion 13. This enlarged portion 13 is, however, preterably curved. inva rearward direction, somewhat as shown, and it may be made solid to actof itself as a weight, or hollow, after the manner o'li a receptacle, tobe weighted by the placing thereiii of articles oi merchandise, mailmatter or the like in su'l'iicient amount.

The supporting member or bracket 11 is to be rigidly braced in itssecured position at the under side oi the fuselage a by means of anumber oil? members or rods i l, and has its lower end formed to provide a recess or socket to seat the upper reduced end portion 15 oilthe member 10 therein, when. the latter is disposed in vertically alinedrelation therewith. in which position the member is sustained, when theaeroplane is in flight, by means oi a coil spring or the like 16. Thisspring 16 has one end secured in an eye or the like 17 at the :torwardside oi the member 10 at a point below the upper end thereof and itsupper end in an eye or the like 18 secured in the lower side of thefuselage a at a point in the plane of the longitudinal. center of thelatter and "forwardly of the stupportin member or bracket 11.

In the operation oi. the stabilizing device, as thus constructed andarranged, and with the aeroplane in position oi: take-oil from theground surtace, the member 10 will extend rearwardly beneath thelongitudinal center of the fuselage a, with its enlarged free end 13resting on the grom'id. Now, as the aeroplane is set in motion for thetake-oil", the weighted end 13 of the member 10, will. slide smoothlyalong the ground and thereby offer no impediment to the 'l'mrwardmovement of the aeroplane. The part 13 continues in contact with theground surface until the aero plane rises in its take-0ft, and as itbegins to rise, the spring 16 acts to draw the member 10 towards thevertical. and, when the aeroplane has risen to a height where the part13 is barely touching the ground or is entirely clear thereof, thespring 16 causes the latter to assume full vertical. position with thereduced end portion 15 fully seated within the recess or socket in thelower end of the member of bracket 11. In this position, the member 10forms a rigid T with the aeroplane in flight.

\Vhen the aeroplane comes to a landing position, the enlarged end 13 ofthe member 10 contacts the ground surface and bends in a rearwarddirection, causing the upper reduced end 15 thereof to disengage fromthe recess or socket in the member or bracket 11. During the continuedlanding flight of the aeroplane, the lower end of the member 10 trailsalong the ground surface and swings towardsa horizontal position as theaeroplane comes to rest.

Thus, it is to be seen that the device, when sustained in the verticalposition during flight of the aeroplane, acts to counter-balance anytendency of the aeroplane to nose-divc or tail-spin, and, also, in itsapplication to commercial or other types of passenger carryingaeroplanes, it provides an effective means against stunt flying on thepart of irresponsible aviators and otherwise reduces accidents toaeroplanes operated by the less experienced aviators to a minimum.

It is to be noted that the stabilizer will vary in size in proportion tothe size of the aeroplane with which it is to be used, and the shorterthe member 10, the greater should be the weight of the lower enlargedend thereof, and, conversely, the longer the member 10, the weight ofthe lower end 13 thereof should be decreased accordingly, also that thelower end of the supporting member or socket 11 will be flared slightlyin a forward direction, as at 19, to give clearance to the upper mentsthereof to seat and unseat the reduced portion 15 in and from theopening provided for its reception.

It is also to be noted, that in the case of engine trouble or stoppage,or the drop o I an aeroplane in flight in an air pocket, it will bepractically impossible for the aeroplane to side-slip, turn over ordive, so that it must volplane or parachute, as the case may be, tosafety.

\Vithout further description, it is thought that the features andadvantages of the invention will be readily apparent to those skilled.in the art, and it \vlll of course he understood that changes in theform, proportion and minor details of construction may he resorted to,without departing from the spirit of the invention or its scope asclaimed.

lVhat is claimed is A stabilizingdevice for aeroplanes comprising asupport secured at the lower side of the fuselage of an aeroplane at thecenter of balance thereof, an elongated rigid member hingedly connectedat one end to said support for rearwardswinging n'iovements only fromthe verti al, means fo automatically moving said member from arearwardly directed position to the vertical during the take-oil flightof the aeroplane. said support having a socket in its lower end to seatthe upper end of said member therein when the latter is swung tovertically alined position therewil h. and counter-balancing weightmeans carried at the other or lower end. of said member.

PHILIP D. STEAD.

